This application claims the priorities of German applications 199 48 227.6, filed Oct. 6, 1999, and 199 58 743.4, filed Dec. 7, 1999, the disclosures of which are expressly incorporated by reference herein.
The present invention relates to an oil deflector in an oil pan for an internal combustion engine including a first oil deflecting plate and a second oil-deflecting plate between a crankshaft and an oil pan and in which the oil-deflecting plates overlap and form a channel in a particular region.
German Utility Model 74 10 986.7 discloses an oil deflector for an internal combustion engine. This oil deflector comprises an oil pan in which lubricating oil dropping into the oil pan is collected in a sump of the oil pan so as to be guided by an oil pump to the various sections of the internal combustion engine. In order to return the lubricating oil efficiently into the sump, in the known arrangement, provision is made to fasten deflecting plates onto integrally formed supporting surfaces of the oil pan by rivets, welding or similar types of fastening. The oil-deflecting plates are held on pipes or supporting surfaces protruding from the bottom of the oil pan. In order to use one pipe or supporting surface for both oil-deflecting plates, the oil-deflecting plates are held thereon in an overlapping manner. The oil-deflecting plates form oil-stripping edges, by way of a longitudinal edge in each case extending over the entire crankcase, in order to improve the oil separation at the crank assembly.
The known oil deflector has the disadvantage that additional supporting surfaces which protrude from the bottom of the oil pan are required for the fastening of the oil-deflecting plates, and a run-off slope has to be stamped into the oil pan in order to supply the oil to the suction point of the oil pump. Because of the special shaping, the oil pan is complicated to produce and has a large overall height.
The present invention has, as one object, the provision of an oil deflector of the type mentioned above but which is simple to produce and has a low overall height.
This object is achieved, in such an oil deflector, by having at least one longitudinal edge of the second oil-deflecting plate form a main oil scraper edge, and, in the particular region in which the oil-deflecting plates overlap, by arranging ribs between the oil-deflecting plates to guide oil in a direction of a suction point formed in the oil pan.
Several advantages of the subject matter of the invention can be seen, since an oil-deflecting device is provided which orientates the direction of the oil particles thrown off from the crank assembly, and the tangential impulse of the oil particles is changed into an impulse in the direction of the suction point of the oil pump. The air flow produced by the crank assemblies is used as a carrier air flow for transporting the oil in the direction of the suction point of the oil pump. The gradient of run-off slopes can be minimized or completely eliminated as a result, and the oil-deflecting device can be of compact design with a minimized overall height.
The oil-deflecting device is advantageously formed from two oil-deflecting plates extending in a strip-shaped manner over the length or over a partial length of the crankcase of the internal combustion engine. By way of one of their longitudinal edges in each case, the oil-deflecting plates rest here on opposite borders of the oil pan or of the crank housing, while their respectively other longitudinal edge extends in the crankcase of the internal combustion engine. The oil-deflecting plates overlap in the crankcase, the plates being at a distance from one another in the overlapping region and forming a channel for conducting oil chrough. The oil-deflecting plates, as viewed in the cross section of the oil deflector, are first of all guided horizontally from both borders of the oil pan and follow, at a distance, the contour of one or two connecting-rod arches of the internal combustion engine. The first oil-deflecting plate, as viewed in the direction of rotation of the crankshaft, is mounted here upstream of the second oil-deflecting plate and reaches under the latter, forming a channel, in the overlapping region. The second oil-deflecting plate forms, by way of its longitudinal edge which extends in the crankcase, a main oil scraper edge. In the region in which the oil-deflecting plates overlap, ribs, which are preferably strip-shaped, are guided from the first oil-deflecting plate to the second oil-deflecting plate, the ribs being orientated in the direction of the suction point of the oil pump by the main oil scraper edge. The ribs are arranged at discrete distances apart, preferably parallel to one another, and, together with the first and the second oil-deflecting plate, form channels. Instead of the ribs, it is also possible to use other elements which act in a flow-aligning manner, such as tubes or the like.
The oil-air flow produced by the rotation of the crankshaft is conducted through these channels, the oil being moved in the direction of the suction point of the oil pump by way of the ribs and by way of the air flow. The ribs preferably serve to connect the first and second oil-deflecting plates, resulting here in a flexurally rigid, box-shaped oil-deflecting device which does not require any further support in the crankcase. As a result, the oil pan itself can be configured such that it is simple and cost-effective in its shaping, since pipes or supporting surfaces and conducting ribs on the bottom thereof can be dispensed with. It may be expedient to form at least the first oil-deflecting plate or even the entire oil-deflecting device in one piece with the oil pan, for example from a light metal casting. Secondary oil scraper edges can be arranged on the first oil-deflecting plate, in each case in the region of the crank assemblies arranged directly above the latter, over the respective width of the corresponding crank assembly. The scraper edges scrape off oil coming off from the crank assembly and pass it to the oil pan. The secondary oil scraper edges are preferably aligned parallel to the longitudinal central axis of the oil-deflecting device and are formed by strip-shaped apertures in the first oil-deflecting plate. The apertures are surrounded by stiffening elements which are U-shaped in outline and in which, also, through holes penetrating the first oil-deflecting plate are arranged. Attached opposite the longitudinal central axis of the oil-deflecting device, on the second oil-deflecting plate, are stiffening elements which are U-shaped in outline and whose legs likewise extend from the oil-pan boundary towards the longitudinal central axis of the oil-deflecting device. Through holes which serve to receive tie rods are guided through the said legs and through the second oil-deflecting plate. The oil-deflecting device is secured to the engine block of the internal combustion engine by way of the tie rods.
Apertures are arranged between the stiffening elements on the first and second oil-deflecting plates. These apertures can be circular or elliptical in outline and serve to minimize the weight of the oil-deflecting device and as a flow-off opening for the air blown in between the oil pan and the oil-deflecting device by the crank assembly. Instead of these apertures, it is also possible for bead-like depressions to be provided which cover the bearing shells of the crank assembly.